Means for determining the dip of strata



June 24, 1930. c, c, THOMPSON 7 1,766,202

MEANS FOR DETERMINING THE DIP 0F STRATA Filed Sept. 22. 1924 C/m/aas CT 77/0 50 ATTQQNBY Patented June 24, 1930 "UNITEDWSIATES PATENT; OFFICE was no: DE ZZZZ I NTN: 11 OZ' ZZZ ZT Application filed September 22, 1924. Serial No. 739,151.

My present invention comprises a method string of pipe such as is used in rotary drillof and means for determining the dip of ing, the joints or sections of this pipe being strata penetrated at a depth below the surshown as connected by couplings 12 and the face of the earth; and it is an especial oblower end .thereof being provided with a ject of this invention toprolvide a method sub 13, securing the same to a bit 14, as

suitable for use in thelocation of anticlinal shown as provided with a conveniently seppockets, or the like, from which a flow of arable coupling section 15 and as provided oil may be expected. at its lower end 16 with a substantially cir- It is an object of this invention to provide cular row of cutting teeth. The coring bit 10 a dip-determining method and means suit- 14 or its equivalent may be rotated through 00 able for use in conjunction with, for examthe string 11 by any .usual or preferred ple, a rotary drilling organization including means such as a rotary table 17 provided a core barrel; anda preferred embodiment with slips 18, the entire string being supof my invention may involve the use of a ported in a usual manner, as in part by a 5 core barrel in'which a core .is intended to swivellhead 19, or its equivalent. 06 stand stationary andv integral with the Although I may employ any preferred.

ground rock during the cutting of the same type of coring bit, I have shown in Fig. 2 and up to the moment of its withdrawal, a bit consisting essentially of a steel tube this core barrel being however adapted ultior shell 14, shown as cut square across at mately to separate and lift the core, and its upper end and in internal threaded en- 7 means being provided and precautions begagement with the separable section 15, the ing taken to make sure that the original latter being shown as provided with a pin orientation relatively to a reference plane or nipple 20, for engagement by a usual box (such as, for example, a meridian plane,) in the sub 13. The teeth at the lower end may be subsequently ascertained. of the tube 14 are preferably cut and set as Other objects of my invention will appear best indicated in Fig. 5, alternate teeth 16" from the following description of an illusbeing bent outwardly in a manner favorable trative embodiment thereof, taken in conto suitable clearances on the outside of the nection with the appended claims and the shell 14, and inwardly projecting teeth 16 0 accompanying drawings, in which being substantially vertical, but provided Fig. 1 is a sectional view showing in elewith a slight inward set, permitting a clearvation, but with parts broken away, an or! ance between the inner surface of the shell ganization suitable for use in the prac ifze and the outer surface of a core. It will be of my invention. understood from Fig. 2 that the teeth 16 Fig. 2 is a sectional view] illust ating a are also adapted to be bent to a core engagsimple type of core barrel in the act of reing and breaking position by the applica movin a sample core, parts of the barrel tion of a suitable downward pressure upon being roken away. the coring bit and the inside of the shell Fig. 3 is a bottom plan view, taken as in- 14. Suitable clearances on the inside are 4 dicatedby the/arrow 3 of Fig. 2. of especial importance, in order to make 0 F g; 4.- is/af-plan View of a collar such as sure that frictional contact with the upwardmay optionally be employed in ascertaining 1y projecting core 21 shall not prematurely the orientation of a string of drill pipe probreak the same from the ground rock, or vided with a coring bit. occasion a disturbance of the strata or con- 45 Fig. 5 is a sectional elevation similar to stituent materials thereof. the lower-part of Fig. 2, but showing the lVhen the downward advance of the string teeth in a core cutting position. shall indicate the cutting of a core of suit- Referring to the details of that specific able length, the core may be separated or 3 embodiment of my invention chosen for broken from the ground, as by discontinuing purposes of illustration, 11 may be a usual rotation of the drill and then causing the same to sustain the entire weight of the string, the inwardly projecting teeth 16 then acting as chisels, with a lifting or severing effect, as illustrated in Fig. 2.

In order to ascertain the dip of any strata comprised in the core 21, I may employ any suitable means for indicating, in a manner permitting exact observation, the orientation of the string 11 and the shell 14, serving as a core barrel, relatively to a plane of reference. For example, I may provide the uppermost section 11 of drill tubing with a mark 22, this mark 22 being immediately above or having a known relationship to' a mark 23, placed externally on the core barrel,the latter mark being optionally carried across the line separating the head section 15 therefrom, and all couplings being optionally marked in a similar manner; and I may provide on or opposite the upper section 11 any suitable means for determining the orientation thereof after the string has been relieved of torsional strain and before lifting operations are commenced. For example, assuming the mark 22 to be directly above the mark 23, I may place upon the section 11 a collar 24, such as is shown in Fig. 4, this collar being shown as graduated in degrees and as rotatable upon the section 11" in such manner that its zero may be brought opposite any suitable point of reference, such as a fixed mark 25 indicating true or magnetic north. If, after the collar is so adjusted as to bring its zero to the north, a note is made as to the relative position of the mark 22, carried by the section 11*, it will be obvious that, even though no pains may have thereafter been taken to preserve the orientation of the string during the separation of the sections or stands thereof, the shell 14 may be ultimately restored to its true or original orientation, as by positioning the removable collar 24 concentrically thereon, with the mark 23 exactly opposite the position in which the mark 22 was previously\ noted, and then again bringing the zero of the collar to the exact north. The core may be removed by simply holding it down on a horizontal surface or otherwise preserving its orientation while the shell 14 is separated therefrom. The core may thereafter be studied in a restored orientation, reproducmg itsoriginal or natural position in the earth, the dip of any strata therein being ascertainable by direct observation and measurement. As a matter of convenience, true or magnetic north may optionally be marked directly on the core, as by a vertical line N, in order to facilitate a study thereof at a remote point, such as a shop or laboratory, both the direction and angle of dip being noted.

It will be obvious that a string 11 may be nitiall provided, during the assembly thereo and as each joint is completely tightened, with a series of marks in the same vertical line; but I consider it advantageous to use a plumb-line or to make renewed or confirmatory observations in carrying a line or series of marks relatively downwardly on a string of pipe during the disassembly of the same into sections or stands; and this marking during withdrawal and disassembly may be a sufficient measure, available even when the coring drill has not initially been marked.

I require no complicated means for the practice of my invention, it being possible to rely upon a mark 25 scratched on a derrick floor or upon an arm 28 and used in conjunction with, for example, a crude protractor, to indicate the final position (relatively to the plane, of reference indicated by the mark 22, or its equivalent) of an additional mark 26, which may be placed upon the section 11 opposite the mark 25, after the string has come to rest; but I have shown the rotatable and removable collar 24 as provided with a compass 27, the employment of which may obviate the necessity for the use of means such as the arm 28 to carry the mark 25; and I have shown this compass as provided with degree marks, in order that, if desired, the collar may be left in a fixed position upon the section 11*, or its equivalent, and with its zero point opposite the mark 22,--readings being then taken from the figures on the compass, shown as graduated in an opposite direction.

Although I have herein described one complete embodiment of my invention, it will be understood that various features thereof might be independently employedand also that various modifications might be made, by those skilled; in the art, without the slightest departure from the spirit and scope of my invention as the same is indicated above and in the following claims." In these claims, I employ the term dip as referring to both the amount and the direction of inclination in relation to a horizontal plane o r to another plane'or planes of reference.

I claim as my invention:

1. An organization for ascertaining the direction. of dip of unexposed strata, com- 5 prising an operating string provided at its lower end with a core barrel for cutting a core without disturbing the original orientation thereof; and oriented means having a poipt of reference thereon, said oriented means being separate from said drill string, and said drill string having a series of. marks thereon in predetermined azimuthal relation for cooperating with said point of reference to determine the original orientation of said core.

2. An organization for ascertaining the direction of dip of unexposed strata, comprising: an operating string provided at its lower end with a core barrel for cutting a core without disturbing the original orientation thereof; and oriented means having a point of reference thereon, said oriented means being in a fixed position and separate from said drill strin and said drill string having a series of marks thereon in predetermined azimuthal relation for cooperating with said point of reference to determine the original orientation of said core.

8. An organization for ascertaining the direction of dip of unexposed strata, comprising: an'operating string provided at its lower end with a core barrel for cutting a core without disturbing the original orientation thereof; and a'fixed oriented pointer,

suitably mounted above the ground surface relative to said drill string, said drill string having a series of marks thereon in predetermined azimuthal relation for cooperating with said point of reference to determine the original orientation of said core.

In testimony whereof, I have hereunto set my hand at Carpinteria, California, this 13th day of September, 1924.

CHARLES C. THOMPSON. 

